/*
 * Copyright (C) 2009,2010 University of Paderborn, Computer Networks Group
 * Copyright (C) 2009,2010 Christian Dannewitz <christian.dannewitz@upb.de>
 * Copyright (C) 2009,2010 Thorsten Biermann <thorsten.biermann@upb.de>
 * 
 * Copyright (C) 2009,2010 Eduard Bauer <edebauer@mail.upb.de>
 * Copyright (C) 2009,2010 Matthias Becker <matzeb@mail.upb.de>
 * Copyright (C) 2009,2010 Frederic Beister <azamir@zitmail.uni-paderborn.de>
 * Copyright (C) 2009,2010 Nadine Dertmann <ndertmann@gmx.de>
 * Copyright (C) 2009,2010 Michael Kionka <mkionka@mail.upb.de>
 * Copyright (C) 2009,2010 Mario Mohr <mmohr@mail.upb.de>
 * Copyright (C) 2009,2010 Felix Steffen <felix.steffen@gmx.de>
 * Copyright (C) 2009,2010 Sebastian Stey <sebstey@mail.upb.de>
 * Copyright (C) 2009,2010 Steffen Weber <stwe@mail.upb.de>
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the University of Paderborn nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package netinf.node.resolution.iocaching.impl;

import netinf.common.datamodel.Identifier;
import netinf.common.datamodel.InformationObject;
import netinf.node.resolution.ResolutionInterceptor;
import netinf.node.resolution.ResolutionService;
import netinf.node.resolution.StorageService;

import org.apache.log4j.Logger;

import com.google.inject.Inject;

/**
 * The Class IOCacheImpl.
 * 
 * @author PG Augnet 2, University of Paderborn
 */
public class IOCacheImpl implements ResolutionInterceptor {

   private static final Logger LOG = Logger.getLogger(IOCacheImpl.class);

   private final StorageService storageService;

   @Inject
   public IOCacheImpl(StorageService storageService) {
      this.storageService = storageService;
   }

   @Override
   public InformationObject interceptGet(InformationObject io) {
      // Looking whether already stored
      InformationObject cachedInformationObject = get(io.getIdentifier());
      if (!io.equals(cachedInformationObject)) {
         LOG.info("Cache INSERT: " + io);
         storageService.put(io);
      } else {
         LOG.info("Cache already contains same IO");
      }

      return io;
   }

   public InformationObject get(Identifier id) {
      InformationObject io = this.storageService.get(id);
      if (io == null) {
         LOG.info("Cache MISS for identifier: " + id);
         return null;
      } else {
         LOG.info("Cache HIT for identifier: " + id);
         return io;
      }
   }

   // FIXME dirty hack to get the IO cache working
   public ResolutionService getRS() {
      return (ResolutionService) storageService;
   }

}
